The New Zealand Plant Conservation Network

Species

Corybas iridescens

Etymology

Corybas: helmet flower
iridescens: Becoming iridescent (from the Latin iridis, meaning the rainbow)

Common Name(s)

Spider Orchid, Big Red

Current Conservation Status

2012 - Not Threatened

Conservation status of New Zealand indigenous vascular plants, 2012
The conservation status of all known New Zealand vascular plant taxa at the rank of species and below were reassessed in 2012 using the New Zealand Threat Classification System (NZTCS). This report includes a statistical summary and brief notes on changes since 2009 and replaces all previous NZTCS lists for vascular plants. Authors: Peter J. de Lange, Jeremy R. Rolfe, Paul D. Champion, Shannel P. Courtney, Peter B. Heenan, John W. Barkla, Ewen K. Cameron, David A. Norton and Rodney A. Hitchmough. File size: 792KB

Previous Conservation Status

2009 - Not Threatened
2004 - Not Threatened

Authority

Corybas iridescens Irwin et Molloy,

Family

Orchidaceae

Flora Category

Vascular - Native

Structural Class

Orchids

Synonyms

Corysanthes iridescens (Irwin et Molloy) Szlach.; Nematoceras iridescens (Irwin & Molloy) Molloy, D.L.Jones et M.A.Clem.

Distribution

Endemic. North, South and Chatham Islands.

Habitat

Coastal to montane (up to 1100 m a.s.l.). Favouring base rich substrates, especially calcaerous mudstones, siltstones (both known as Papa rock), and limestone but also on basalt. Usually in, or near seepages or on the margins of slow-flowing streams

Features

Terrestrial, tuberous, glabrous, summer-green herb forming extensive colonies. Tuberoids globose to ellipsoid on extended roots. Leaf solitary, fleshy, more or less subcoriaceous, usually spreading and held flat to the ground surface; shortly petiolate, petiole 3.0-10.0 x 1.5-3.0 mm; lamina 20-40x 15-35 mm, or larger, ovate-oblong or bluntly wedge-shaped, often pandurate, squared and apiculate at apex, with apiculus decurved, rounded and cordate at base; midrib grooved above, ridged beneath; leaf colour dull dark green above with purple flecks on margins, on midrib, or overall, silvery beneath. Flowers 1(-2), 12-20 mm long, dark red-green, dominated by labellum, dorsal sepal and long filiform petals and lateral sepals; peduncle 4-5 mm long. Ovary 4-8 mm long, green or cream, purple-flecked, curved, subtended by two unequal floral bracts, the smaller 3-5 mm long, linear-subulate, terete the larger equal to or exceeding the ovary, 7-10 mm long, lanceolate, green flecked with purple. Dorsal sepal extending well past labellum 20-35 x 8-12 mm, narrowly ovate in outline when flattened, concave, cucullate and arching over the labellum tube, with apex usually recurved; green spotted and/or striped with purple. Lateral sepals 50.0-70.0 x 0.5-1.0 mm at widest point; filiform, greatly exceeding labellum; translucent white with purple striations, horizontal to suberect and projecting forwards and outwards; suberect to erect and spreading; channelled, and twisted. Petals 40.0-60.0 x 0.5-1.0 mm at widest point, slightly shorter than lateral sepals, filiform, greatly exceeding labellum, translucent white with purple striations, horizontal to suberect, projecting forwards and outwards; channelled, auriculate on the base of the column. Auricles short, projecting downwards and forwards, with apertures 1.5-2.5 mm across. Labellum conspicuous, dark red, maroon-red to almost black, sometimes striped with green at front, iridescent when wet; labellum tube 5-7 mm long, erect at first then abruptly deflexed through 160-180 degrees, and expanding into the lamina with a prominent bead-like callus in throat of tube at bend; lamina 10-20 x 10-15 mm, broadly ovate to orbicular; upper margins folded inwards, mostly overlapping; lower surface spreading, deflexed against ovary; with margins erose-papillose, and a long median apiculus; inner surface with dense, minute, retrorse papillae and ridged veins; throat of labellum tube high on lamina. Column 3-4 mm long, broadest and ridged at base, inclined backwards, minutely winged. Stigma scutiform to oblong, 1 mm diameter, concave. Anther 1 mm, purple-obtuse. Pollinia 4, united in pairs, 1.0 x 0.7 mm, oblong, mealy, yellow. Capsule 12-20 x 5-7 mm, elliptic, initially pale green later brown, on greatly elongated peduncle.

Similar Taxa

Distinguished by the combination of shortly petiolate, broadly wedge-shaped, usually spotted leaves; broad dorsal sepal; subequal petals and lateral sepals; abruptly deflexed, dark red, almost black labellum, which is strongly iridescent when wet; and by the prominent bead-like callus at the entrance to the labellum tube.

Flowering

August - November

Flower Colours

Green,Red / Pink

Fruiting

October - January

Propagation Technique

Difficult - should not be removed from the wild.

Threats

Not Threatened

Chromosome No.

2n = 36

Endemic Taxon

Yes

Endemic Genus

No

Endemic Family

No

This page last updated on 16 Jan 2016